When she was torpedoed, Thornliebank was carrying ammunition and she blew up in a great explosion, killing all on board. (66 crew members and 9 gunners).
So big was the explosion that debris from the ship fell on the U-boat and even injured one of the Germans.
To their amazement, the next day, the Germans found a 10 cm shell, which had been blown from a distance of 1.200 metres onto the conning tower. Thornliebank SS was a British cargo steamer of 5,569 grt that was owned by the Bank Line Ltd. On the 29th November 1941 she was torpedoed and sunk by German submarine U-43 when on route from Barry for Suez with a general cargo.